This challenging question tests your understanding of cache. Consider the following C code: int A[16]; int B[16]; int m; ... //A large chunk of code that does NOT access //arrays A and B. ... for (int i=0; i<10; i++) { for (int j=0; j<16; j++) { B[j] = m * A[j] + B[j]; } } Assume this program runs on a 32-bit machine, i.e., the CPU loads/stores 4 bytes from memory in one go. This machine has a 16-bit memory address, and each memory block stores 16 bytes. This machine has a direct-mapped data cache with 16 cache lines. Array A starts at address 0, and B starts at address 256 - both arrays begin at a memory block boundary. Each element of arrays A and B occupies 4 bytes. The values of i, j, and m are stored in CPU registers. What is the total number of data cache misses (including compulsory misses)

This challenging question tests your understanding of cache. Consider the following C code: int A[16]; int B[16]; int m; ... //A large chunk of code that does NOT access //arrays A and B. ... for (int i=0; i<10; i++) { for (int j=0; j<16; j++) { B[j] = m * A[j] + B[j]; } } Assume this program runs on a 32-bit machine, i.e., the CPU loads/stores 4 bytes from memory in one go. This machine has a 16-bit memory address, and each memory block stores 16 bytes. This machine has a direct-mapped data cache with 16 cache lines. Array A starts at address 0, and B starts at address 256 - both arrays begin at a memory block boundary. Each element of arrays A and B occupies 4 bytes. The values of i, j, and m are stored in CPU registers. What is the total number of data cache misses (including compulsory misses)

Name: Q5 Cache Performance Analysis This challenging question tests your und
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Description: Q5 Cache Performance Analysis This challenging question tests your understanding of cache.Consider the following C code:int A[16]; int B[16]; int m; ... //A large chunk of code that does NOT access //arrays A and B. ... for (int i=0; i<10; i++) { for

Systems Architecture

7th Edition

ISBN:9781305080195

Author:Stephen D. Burd

Publisher:Stephen D. Burd

Chapter6: System Integration And Performance

Section: Chapter Questions

Problem 22VE

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Q5 Cache Performance Analysis This challenging question tests your understanding of cache. Consider the following C code: int A[16]; int B[16]; int m; ... //A large chunk of code that does NOT access //arrays A and B. ... for (int i=0; i<10; i++) { for (int j=0; j<16; j++) { B[j] = m * A[j] + B[j]; } } Assume this program runs on a 32-bit machine, i.e., the CPU loads/stores 4 bytes from memory in one go. This machine has a 16-bit memory address, and each memory block stores 16 bytes. This machine has a direct-mapped data cache with 16 cache lines. Array A starts at address 0, and B starts at address 256 - both arrays begin at a memory block boundary. Each element of arrays A and B occupies 4 bytes. The values of i, j, and m are stored in CPU registers. Assume we change the cache configuration to be 2-way set-associative. This new data cache has 8 sets and 16 bytes per line. The cache uses a Least Recently Used (LRU) replacement policy. How many data cache misses (including…
Computer Science Consider a direct-mapped cache with 8 lines, each holding 16 bytes of data. The cache is byte-addressable and the main memory consists of 64 KB, which is also byte-addressable. Assume that a program reads 16KB of memory sequentially. Answer the following questions:a) How many bits are required for the tag, index, and offset fields of a cache address?b) What is the cache size in bytes?c) What is the block size in bytes?d) What is the total number of blocks in main memory?e) How many cache hits and misses will occur for the program, assuming that the cache is initially empty?f) What is the hit ratio?g) Give an example virtual address (in BINARY) that will be placed in cache line 5.
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Describe the challenges that arise when attempting to build a cache replacement approach that works for all address sequences.
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